1. Field of the Invention
The invention relates to apparatus for installing and removing elongated, cylindrical fluorescent bulbs into or out of their customary supporting fixtures. The invention has particular application in fluorescent lighting systems involving axially directed, spring type retaining sockets for mounting tubular fluorescent bulbs.
2. Summary of the Prior Art
As is well known, the installation and removal of fluorescent bulbs is usually accomplished with much inconvenience. In the normal situation, fluorescent bulbs are supported in fixtures at an overhead location out of reach of the normal size person. Hence, an elevated platform or ladder is needed to place the maintenance person within reach of the particular fixture needing a bulb change. Since many fluorescent bulbs range in length from six to eight feet, it is difficult for the maintenance person to climb up a ladder holding the bulb, then align one end of the bulb with the spring type retaining socket, apply an axial force to the bulb to compress the socket, and then swing the other end of the bulb into engagement with the other socket.
It has been previously proposed that grasping units for holding a fluorescent bulb be secured to the end of an elongated handle to permit the replacement of the bulb without resort to a ladder. Bulb grasping units of this type are shown in the following U.S. Patents:
______________________________________ #2,393,880 Beard #2,589,642 Stueland #2,855,238 Ford #3,101,212 Cater #3,929,365 Hunt et al ______________________________________
In all of the aforementioned prior art patents, except the Hunt et al patent, elaborate mechanisms are provided generally incorporating two semi-cylindrical grasping elements which are moved relative to each other in surrounding, clamping relationship relative to a fluorescent bulb by the operation of a complex linkage. Obviously, these constructions are expensive to manufacture and require frequent repair due to the number of moving parts involved in such prior art apparatuses.
The Hunt et al U.S. Pat. No. 3,929,365 discloses a simpler arrangement for grasping a fluorescent bulb, having either one or two connector prongs, comprising a semi-cylindrical gripper. A complex coupling is provided between the gripper and the operating handle to permit rotation of the bulb for insertion of a two prong type. The Hunt et al construction is obviously expensive to manufacture.
It is readily apparent, therefore, that a fluorescent bulb handling mechanism involving a minimum of movable parts, yet assuring the firm securement of the bulb during an installation or removal operation, would be a highly welcomed mechanism for installing or removing elongated fluorescent bulbs.